Legionnaires' disease cases spike 143% in Michigan

Health officials across the state are trying to determine what's causing a 143% increase in cases of Legionnaires' disease, a respiratory infection that can be deadly, especially for people with weak immune systems.

"In the warm months, there is an increase in Legionnaires'," said Jennifer Eisner of the Michigan Department of Community Health. "At this point, no common source has been identified."

In June and July, 73 cases were confirmed. In the past three years, the average number of cases during those months was 30....

...Legionnaires' became an issue in the Flint water crisis. State health officials confirmed 91 cases, including 12 deaths, from the disease in Genesee County in a 17-month period in 2014-15. The cases spiked after the city switched its water source from the Detroit water system to the Flint River in April 2014.

Janet Stout, an associate professor at the University of Pittsburgh Swanson School of Engineering who has 30 years of experience studying the disease, concluded the problems with Flint's water were related to the increase in Legionnaires' cases — although she can't prove it. “It is like an emperor’s new clothes situation,” Stout told the Free Press last year. “Somebody has to say it.”

She said it's a "reasonable conclusion," given the link between poor water quality and Legionnaires' disease in scientific studies done elsewhere.